1. Field of the Invention
The present invention relates to a fluorescent lamp such as a hot cathode fluorescent lamp and a method of manufacturing a fluorescent lamp.
2. Description of the Related Art
It has been customary to use a fluorescent lamp using a fluorescent material as a light source.
In particular, since a hot cathode type fluorescent lamp is high in luminous efficiency and brightness, it is used not only as a light source for illumination apparatus but also as a backlight of a liquid-crystal display (LCD).
The hot cathode type fluorescent lamp has an arrangement in which electrodes are provided at respective ends of a glass tube, a gas such as an Ar (argon) gas and mercury are sealed into a space within the glass tube, a fluorescent material being coated on the inner surface of the glass tube (see Cited Patent Reference 1, for example).
[Cited Patent Reference 1]: Official Gazette of Japanese laid-open patent application No. 5-251042
FIG. 1 of the accompanying drawings is a schematic diagram showing an arrangement of one end portion of a fluorescent lamp according to the related art.
Since the related-art fluorescent lamp uses an exhaust pipe to exhaust the inside of the fluorescent lamp upon manufacturing, as shown in FIG. 1, an exhaust pipe 102 still remains in the finished fluorescent lamp 101.
Further, since a lead wire 104 connected to an electrode 3 such as a coil should be provided independently of the exhaust pipe 102, it is not possible to decrease a diameter D of the fluorescent lamp 101.
For this reason, this fluorescent lamp according to the related art may not be applied to a narrow frame type backlight of backlights.
Further, since a diameter d of the exhaust pipe 102 is considerably smaller than the diameter D of the fluorescent lamp 101 (D>d), if the diameter of the exhaust pipe 102 is decreased, then it is frequently observed that conductance of exhaustion will be extremely lowered or that it will become impossible to use the exhaust pipe 102.